relative molecular mass
What relative molecular mass means in Chemistry A-Level, as defined for AQA, OCR.
Definitions of relative molecular mass
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Reference: AQA
The mean mass of one molecule of the substance divided by one-twelfth the mass of one atom of carbon-12.
Applies to molecules and is the sum of the relative atomic masses of all atoms in one molecule.
Topics that use relative molecular mass
- Relative atomic mass and relative molecular mass (AQA A-Level)
- Atomic structure and isotopes (OCR A-Level)
Related terms
- Relative atomic mass
- relative formula mass
- atomic number
- Calculation accuracy
- ionic lattices
- isotopes
- Isotopic abundance
- Isotopic abundance and its effect on the mean
Using relative molecular mass in the exam
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